Gelatin-dynamite explosive



Patented Apr. 24, 1928.

UNITED STATES.

PATENT OFFICE.

ROSCOE SMITH, OF KENVIL, NEW JERSEY, AND ERNEST M. SYMMES, 0F WILMING- TON, DELAWARE, ASSIGNORS TO HERCULES POWDER COMPANY, OF WILMINGTON, DELAWARE, A CORPORATION OF DELAWARE.

GELATIN-DYNAMITE EXPLOSIVE.

N0 Drawing.

For many years the lowest strength of gelatin dynamite made was the .so-called forty per cent gelatin dynamite composed of Per cent. Nitroglycerin, etc 31 Nitrocompounds 2 Nitrocotton 0.6 Sodium nitrate 52.7 Wood pulp 2.2 Corn meal or ivory meal 4.5 Flour or corn starch 3.0 Sulphur 3.0 Chalk 1.0

By successive steps the strength was reduced by cutting down the nitroglycerin content until in later years a so-called twentyfive per cent gelatin dynamite was success- Such a twenty-five per cent gelatin dynamite was considered as low a strength as could be obtained, because if the nitroglyc erin content were lowered still further the mixture would be too dry and stiff to be satisfactory as a gelatin dynamite, could not be packed into shells by any practical machines, and would have an unsatisfactorily low sensitiveness to detonation.

We have discovered that by still further reducing the nitroglycerin content but simultaneously adding more of a liquid of low explosive strength, such as liquid dinitrotoluol, the explosive strength of a gelatm may be reduced to a 20% strength while still leaving sufficient liquid present to avoid the above mentioned ditficulty of too dry, stifl' and insensitive a gelatin. We have also dlscovered that by using non-absorbent carbonaceous materials, which merely retain the gelatinized nitroglycerin-dinitrotoluol mixture on Serial No. 151,243.

their surface, we afford a continuous film on which the wave of detonation can travel throughout the mass. By a study of the individual absorbencies of the ingredients other than the explosive ingredients we have determined just which non-explosive ingredients, and in what proportion of each, should be used to absorb as a surface film the liquid explosives employed. The nonexplosive ingredients that we have added have the characteristic that they do not subsequently, with time, absorb into their mass the liquid explosive, but merely retain the latter on their surface. This facilitates the passage of the wave of detonation through the mass and so maintains indefinitely the sensitiveness to detonation.

As an example of such a composition we give:

Percent. Nitroglycerin, etc 18 Liquid dinitrotoluol 4 Nitrocotton .2 Sodium nitrate 63.3 Sulphur 9 Starch 3.3 Ivory meal 1.2 Chalk 1 This composition has a sensitiveness of 68, a strength of a 20% gelatin dynamite, and works easily through the usual type of packing machines; and since the non-explosive ingredients are non-absorbent, the explosive ingredients are not absorbed into the mass of the non-explosive ingredients.

The percentage of nitroglycerine should not much exceed eighteen per cent, but may be as low as about seventeen per cent. The percentages of liquid dinitrotoluol and nitrocotton should not materially exceed the percentages specified in the example composition, although the proportion of each may be reduced fifty per cent below the percentages specified. The percentage of sodium nitrate may vary from sixty to sixty-five per cent. The percentage of sulphur should not be substantially below that specified in the example composition, but may be increased to twelve per cent. The percentages of starch and ivory meal are variable within Wide limits. Ivory meal may constitute as much as two per cent of the composition, but it may be omitted although. 111 general, the smaller the proportion of ivory meal, the larger should be the proportion of starch, which may, therefore, have a permissible percentage range of from two to five per cent. The percentage of chalk should not vary materially from that specified in the example composition.

It will be understood that in specifying liquid dinitrotoluol as one of the ingredients of the explosive, it is not intended to exclude known equivalents, of which ti'initrotoluol is an example. Potassium nitrate may be substituted for sodium nitrate, but with added cost and without any compensating advan tagc. For starch may be substituted corn flour.

It is well known that in the manufacture of gelatin dynamites, any of the well known nitroglycerines may be employed; for example, trinitroglycerine, tetranitrodiglycerinc. dinitrochlorhydrene. dinitro zlycol, nitrohydrene, or combinations of any two or more of them.

It will be understood that in the claims where specitie substances are set forth, 1t 15 not intended to exclude the use 1n place thereof of known equivalents, of which examples are herein given.

Having now fully described our invention, what we claim and desire to protect by Letters Patent is:

A low strength dynamite explosive comprising the below specified ingredients each within the proportion range specified, namely. nitroglycerin, 1.1 18 per cent; dinitrotoluol, Q-4t per cent; nitrocotton, .1.2 per cent; sodium nitrate, (30455 per cent; sulphur, 9-12 per cent; starch 25 per cent;

and a small proportion of chalk.

In testimony of which invention, 1, Roscoe B. Snn'rn, have hereunto set my hand at Kenvil. N. J on this 23rd day of November, 1926, and I, ERNEST M. Snares, have hereunto set my hand at \Vilmington, Delaware, on this 24th day of November, 1926.

ROSCOE B. SMITH. ERNEST M. SYMMES. 

